There are standard package designs for certain types of military grade DC-DC converters, filters and other electronic circuits such as those shown in FIGS. 1 and 2. The typical prior art for constructing these circuits and assembling them in their packages is shown in FIG. 3. A ring frame 301 (typically Kovar) is welded to a base plate 302 (typically Molybdenum). A ceramic substrate 303 (typically Alumina, Aluminum Nitride, or Beryllium Oxide) is bonded to the base plate using epoxies or solder alloys if the substrate is suitably plated. Electronic components are soldered to the substrate which also contains thick and or thin film conductors. Most of the active microcircuits 304 (e.g. MOSFETs, diodes, control IC's) are soldered or epoxied to the substrate as bare die and wire bonded for connectivity. Magnetic devices 305 (e.g. transformer and inductors) are also surface mounted to the substrate. Input and output (I/O) pins 306 enter and exit the ring frame through holes with hermetic glass seals 307 that also provide electrical isolation between the pins and the ring frame. The I/O pins are wire bonded to the substrate or connected using L shaped brackets. A thin cover 308 (typically stainless steel) is seam soldered or welded to the ring frame in a vacuum so that there are no opportunities for penetration of external corrosive elements that would attack the bare silicon devices inside. The selection of all of the materials are carefully made in order to minimize differences in thermal expansion properties between the silicon of the active microcircuits, ceramic substrate, metal base plate, and glass seals.